Hi Ghost,
I do not have a check to make sure the resulting container can hold the full book. I suggest for the very common ones like the turn in books, that you have one per bag when sorting a high volume. However, that should not cause a crash (also, if you could describe crash.. i.e. is the client crashing and you get an error message, does oEUO crash, or does the script just 'break'?) but cause the script to break because it cannot move the book back to the original reward bag.
I ran this script on 3.7k bods without a single problem. I did however, have it set up with one book/bag for the common ones, and had one bag with the higher end rewards in it.
If you are having issues with the client actually crashing, could you try increasing the lagOffset to 250 or 500? It will slow the script down by increasing wait times between drags/drops. However, that is the only command being sent to the client other than mouse clicks to empty the bod books.
If you're experiencing an actual client crash, then you're not the only one experiencing client crash issues, but I do not know how to trouble shoot it since I cannot reproduce the problem on my machine. I will ask some experienced scripters if they could try the script to see if they can reproduce the client crashes.